Benign Breast Cyst in a Young Male.

Simple benign breast cysts are commonly diagnosed in female breasts and may present as palpable masses. However, they are extremely uncommon in the male breast and are rarely reported in the literature. Here, we report a case of a simple benign cyst of the breast in a relatively healthy 37-year-old man. The patient initially presented with a palpable 2-3 mm tender left breast lump. Further evaluation with mammography and ultrasound revealed a mass most consistent with a simple benign cyst. However, considering the rarity of breast cysts in males, the lesion was biopsied to rule out malignancy. Pathology results from ultrasound-guided core needle biopsy demonstrated fibro-adipose tissue with a benign cyst lined by foamy cells with apocrine features, consistent with a diagnosis of a benign epithelial cyst and concordant with the radiological findings. To our knowledge, this is the youngest case of a benign breast cyst in a male that has been reported in the literature. In this case report, we discuss the typical features and presentation of breast cysts in males, associated imaging findings on mammography and ultrasound, and the necessity for pathological confirmation with biopsy in this population.